Tag Archives: galls

Plant galls: how insects co-opt plant development to build themselves homes

(Image credit: Lahvak via Flicker/CC BY-NC-SA)

Note: This is a science outreach piece belonging to a series I wrote for the newsletter of the CC BY-SA 88x31Fredericton Botanic Garden. I’d be happy to see it adapted for use elsewhere and so am posting the text here under a CC BY-SA 4.0 license. If you use it, though, I’d appreciate hearing where and how.


With winter upon us, a walk in the Garden has gotten less colourful: nothing is in flower, and most plants have died back or dropped leaves. But I hope you’ll see this as an opportunity to notice things that aren’t as easy to spot in the full flush of summer vegetation. Plant galls are such a thing, and they’re a piece of natural history that especially fascinates me. A “gall” is an abnormal growth on a plant, caused by an attacking natural enemy such as a bacterium, a virus, or an insect herbivore. I’m a particular fan of insect galls, because they tip us off to a complex web of developmental, ecological, and evolutionary interactions between the insect and its plant host. Continue reading